Grant: Project Grant

Puberty is an essential developmental process in mammals. Puberty marks the onset of sexual maturation and is associated with increased incidence of depression and anxiety. Two risk factors for the development of depression are psychosocial stress and pubertal timing. Importantly, psychosocial stress can itself shift pubertal timing. Puberty onset, susceptibility to stress, and risk of depression all differ between males and females. For these reasons understanding sex specific mechanisms underlying how social stress influences pubertal timing has tremendous importance for human health. The naked mole-rat (NMR) is a unique rodent exhibiting extreme socially-mediated reproductive suppression. NMRs reside in large colonies of adults who remain in a pre-pubertal state due to the presence of a dominant breeding female known as the queen. In addition to the queen, a dominant breeding male (known as a consort) has also gone through puberty. Most NMRs will never go through puberty unless they are removed from the suppressive cues of their colony. By studying NMRs, we have an exceptional opportunity to learn how social cues influence pubertal timing. Here we will identify genome-wide gene expression patterns as well as modifications to the DNA that turn genes on and off (known as epigenetic changes) in the brain, adrenal glands, and gonads of NMRs. We will also manipulate stress-relevant genes to examine how they influence puberty and gene expression in brain. The goal of our research is to discover sex specific genes that are involved in suppressing puberty in NMRs, which may explain associations between age of pubertal onset, stress reactivity, and risk for psychopathology in humans.